''Protorothyris'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of Early Permian protorothyridid known from

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

and

West Virginia West Virginia is a state in the Appalachian, Mid-Atlantic and Southeastern regions of the United States.The Census Bureau and the Association of American Geographers classify West Virginia as part of the Southern United States while the B ...

of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

. It was first named by Llewellyn Ivor Price in 1937 and the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

is ''Protorothyris archeri''. ''P. archeri'' is known from the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

MCZ 1532, a three-dimensionally preserved

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

and from the referred specimens, which come from four additional individuals, MCZ 2147-2150. All specimens were collected in the Cottonwood Creek site, from the

Archer City Formation The Archer City Formation is a geologic formation in Texas. It preserves fossils dating back to the Permian period. See also * List of fossiliferous stratigraphic units in Texas * Paleontology in Texas Paleontology in Texas refers to paleont ...

, dating to the

Asselian In the geologic timescale, the Asselian is the earliest geochronologic age or lowermost chronostratigraphic stage of the Permian. It is a subdivision of the Cisuralian Epoch or Series. The Asselian lasted between and million years ago (Ma) ...

stage of the Cisuralian

epoch In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured. The moment of epoch is usually decided by ...

, about 299–294.6

million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds. Usage Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago) ...

. A second species, ''P. morani'', was first named by

Alfred Sherwood Romer Alfred Sherwood Romer (December 28, 1894 – November 5, 1973) was an American paleontologist and biologist and a specialist in vertebrate evolution. Biography Alfred Romer was born in White Plains, New York, the son of Harry Houston Romer an ...

1952 Events January–February * January 26 – Black Saturday in Egypt: Rioters burn Cairo's central business district, targeting British and upper-class Egyptian businesses. * February 6 ** Princess Elizabeth, Duchess of Edinburgh, becomes m ...

with its own generic name, ''Melanothyris''. In 1973, J. Clark and

Robert L. Carroll Robert "Bob" Lynn Carroll (May 5, 1938 – April 8, 2020) was an American–Canadian vertebrate paleontologist who specialised in Paleozoic and Mesozoic amphibians and reptiles. Biography Carroll was an only child and grew up on a farm ne ...

recombined ''P. morani'' as a ''Protorothyris'' species. It is known from the

CM 8617, a three-dimensionally preserved skull. It was collected in the Blacksville site, from the Washington Formation (

stage) of

. ''Protorothyris'' was the size of the average lizard, about 30 cm in length.Sumida, S. S. and Martin, K. L. M. (1997). ''Amniote Origins: Completing the Transition to Land''. Academic Press. 510 pp.

References

Permian reptiles of North America Fossil taxa described in 1937 Fossils of the United States Prehistoric reptile genera {{Permian-reptile-stub